Apparatus for electro-plating crankshaft journals



April 1955 H. R. WELLS 2,706,174

APPARATUS FOR ELECTRO-PLATING CRANK-SHAFT JOURNALS Filed April 6. 1951 3 Sheets-Sheet l INVENTOR. HAROLD R. WEL L5 April 12, 1955 H. R. WELLS 2,706,174

APPARATUS FOR ELECTRO-PLATING CRANKSHAFT JOURNALS Filed April 6, 1951 3 Sheets-Sheet 2 INVENTOR. HAROLD R WELLS April 12, 1955 H. R. WELLS 2,706,174

APPARATUS FOR ELECTRO-PLATING CRANKSHAFT JOURNALS Filed April 6, 1951 3 Sheets-Sheet 3 INVENTOR. HAROLD R. WELL5,

United States Patent APPARATUS FOR ELECTRO-PLATING CRANKSHAFT JOURNALS Harold R. Wells, Rocky River, Ohio Application April 6, 1951, Serial No. 219,694

6 Claims. (Cl. 204-212) This invention relates to electro-plating and is essentially concerned with simultaneously depositing plating metal on a plurality of relatively offset journal surfaces.

An example of articles to which my invention may be applied is a crankshaft, and the principal object of the invention is to simultaneously deposit the plating metal on the main bearing journal and connecting rod journal surfaces at the same time.

Other important objects include the attainment of precise dimensional depositing of the metal coating over the entire surface of each journal with a minimum of loss of plating metal and maximum efficiency of use of the plating current for any given thickness of the plating deposit desired.

It has become recognized in practice that the plating of journal bearing surfaces of new crankshafts with a coating of chromium, or the like, and of a predetermined and accurately uniform thickness results in much longer Wearing life.

In previous plating methods the resulting uneven thicknesses of the deposited coatings not only require more time than my method, but because of uneven thickness of the coating, subsequent grinding has been necessary. By the use of my method the plating may be so accurately accomplished that little or no grinding may be required for the finishing of the surfaces.

Another use of the present invention is that of depositing chrome plating, or the like, to build up worn journal surfaces to the extent of several thousandths of an inch, perhaps ten or even twenty thousandths or more, which surfaces are thereafter ground to accurate concentric finished size.

Heretofore, the plating of worn crankshafts has required carefully insulating all of the surfaces other than the journal surfaces preparatory to immersing the crankshaft in a plating bath.

This invention contemplates positioning the plating current-carrying anodes adjacent to the journal surfaces while holding predetermined spacing of the anodes from the journal surfaces. In order to present the entire circumference of both the main journal surfaces and the crank journal surfaces to the nearest positions to the anodes, the crankshaft is revolved about its main axis while stationary anodes maintain a close position to the main journals and, simultaneously, parallel arm anode surfaces follow the moving crank journal surfaces in the spaced relation. Thus, the journal surfaces are progressively presented to closely adjacent points of the anodes during the plating operation.

It thus will be apparent that an important object of the invention is to effect the positioning and spacing of the movable anodes and the associated connecting rod journal surfaces, and to maintain this spaced relation between the anodes and the surfaces while the crankshaft is slowly revolved in the plating bath.

Other objects include so arranging such an apparatus for attaining the foregoing objects that it shall be simple and economical to construct and efficient in operation.

Two forms of apparatus for carrying out the purposes of the present invention are illustrated in the present application. These are both practical and successful and may be considered illustrative of modifications which may be made within the spirit and scope of the present invention.

Other objects and advantages will become apparent "ice in the following description which relates to the accompanying drawings, in which:

Fig. 1 is a somewhat diagrammatic view showing a tank for a plating bath and my apparatus supporting the crankshaft with anodes arranged to effect depositing on both the main bearing and rod bearing surfaces;

Fig. 2 is an enlarged horizontal sectional view showing the positioning of the anodes with relation to the crankshaft bearings, and showing supporting shafts carrying the anodes in section, the plane of the section being indicated by the line 2--2 of Fig. 1, and showing one main journal anode and the relative position of three anodes for three angularly separated rod journals;

Fig. 3 is a plan view of the insulated master crank member and actuator for one set of rod journal anodes being a section on a plane such as indicated by the line 3-3 of Fig. 1;

Fig. 4 is a sectional plan view of an insulating guide plate affording supporting bearings for the crankshaft and anode-carrying shafts, being a section taken on a plane indicated by the line 4-4 of Fig. 1;

Fig. 5 is an elevation of the master crank for actuating the movable anodes, and which is adapted to be attached to the end of the crankshaft, but here shown as removed;

Fig. 6 is a fragmentary view of the crankshaft showing the movable anodes and an actuating member for causing this pair of anodes to follow the movement of the piston rod journals;

Fig. 7 is a horizontal sectional plan showing the nonconducting actuating member for the anodes, the plane being taken on the line 7-7 of Fig. 6;

Fig. 8 is an enlarged sectional detail showing a connecting rod journal, the two anode arms and the actuator of non-conducting material engaging the journal surface below the anode arms;

Fig. 9 is a fragmentary sectional plan taken substantially on the line 9-9 of Fig. 8.

In the following description of the drawings, the same or like parts are indicated by the same referene characters.

A multiple throw crankshaft has main bearings indicated at B, and the eccentric or connecting rod journals as shown at E. The crank or throw portions appear at T. The usual flange F may be suitably attached to a similar flange 1 of a vertical supporting rotatable shaft 2 carried in a frame indicated. at 4.

As stated, the drawings illustrate only the essential operative parts which are shown somewhat diagrammatically inasmuch as for the most part they may be of any suitable construction.

The frame member 4 which serves to support the shaft 2 and the electrode-carrying bus-bar shafts 6, 7, 8 and 9 is in turn intended to be carried on a vertically movable support, not shown, but by which the assembled crankshaft and anode supporting and operating mechanism may be raised from and lowered into the tank 10 containing the plating bath P. The frame 4 may also serve as a conductor or be provided with-means for carrying current from the positive current supply conductor indicated at 15, while the shaft 2 carrying the crankshaft may be provided with a negative currentcarrying contact ring 16, the current being led therefrom through a suitable brush 17 and a conductor indicated at 18.

With the crankshaft C suspended by the shaft 2 in the plating bath, as shown in Fig. 1, the depositing of plating metal onto the main journal surfaces B may be effected by current passing through the bath from main bearing anodes 20, supported on the shaft 6. The anodes 20 preferably comprise forked members having fiat vertical surfaces evenly spaced from opposite sides of the main journal surface B and are shown as carried on arms 21 each of which is rigid with a supporting hub 22 embracing the shaft 6. The shaft may be provided with a key-way for a key 24 carried by the hub and adapted to be pressed tightly toward the shaft 6 to clamp the anode members in adjusted vertical position, as by a screw 25.

On each of the bus-bar shafts 7, 8 and 9 are forked or bifurcated anode members 30, 31 and 32. These anode arms are parallel strips slightly narrower than the bearings, and long enough to permit the rotating movement of the connecting rod journals E while maintaining the spaced relation between the embraced journal throughout its revolution.

Each of these pairs of anode arms 30, 31 and 32 is carried by a hub similar to the hub 22 and designated 33, 34 and 35, respectively, and each of these hubs is provided with a key and a clamping screw for holding the anodes in adjusted vertical position.

The bus-bar shafts 7, 8 and 9 are rotatably and removably held in the frame 4 so that they may oscillate to permit the bifurcated anodes to follow the rod journals as the crankshaft is revolved.

The anodes may be adjusted vertically, and the shafts then placed in their supports on the frame such as indicated at 40 at the upper end of the shaft 8. These bearing supports 40 may comprise any suitable journal with a removable bearing washer and nut as indicated at 41. Thus, the anodes may be located longitudinally on the rod or shaft 8 and clamped in the correct adjusted vertical position for two or more aligned rod journals, and the bus-bar shaft may then be readily attached to the frame.

The particular crankshaft shown has six connectingrod journals and seven main bearing journals, as is usual with such a shaft for an automobile, truck engine, or the like. The central or main bearing journals alternate between the crank throw portions T, and these are arranged in pairs of journal supports. These pairs being aligned two anode members may be in the same angular position extending from the same anode supporting busbar shaft 7, 8 or 9.

The first and sixth journal anodes 32 are shown as carried on the bus-bar shaft 8. The two middle connecting-rod journals may have their anodes 31 supported on the bus-bar shaft 7, and the anodes 30 for the journals in the second and fifth positions may be supported by the shaft 9. Where an engine crankshaft, such as shown, has six bearings arranged in pairs, these pairs are positioned at 120 spacing about the main axis.

With the shaft suspended in the position shown, the supporting shaft 2 may be slowly revolved, thus turning the crankshaft on its main axis revolving the rod journals. It will be seen that it is now necessary to cause oscillation of the anode supporting shafts 7, 8 and 9 in such timed relation as to assure the pairs of arms remaining in uniformly spaced relation from the journal surfaces, that is, out of contact and with the journals spaced midway between the parallel anode arms. The main bearing journal surfaces may stand between the stationary anode arms while its supporting bus-bar shaft 6 remains fixed.

With current supplied to the anodes passing through the plating bath which may contain chromium oxide, for example, to the journal surfaces and thence to the crankshaft which forms the negative or cathode, it will be seen that with the crankshaft revolving all of the surfaces will be progressively presented to the nearest points of proximity to the anodes, thus effecting an evenly distributing depositing plating action.

In order to effect the oscillation of the anode supporting shafts 7, 8 and 9 in timed relation with the movement of the rod journals, various mechanical means may be utilized. However, a very simple and most effective means for accomplishing this purpose is that of providing a non-conducting master crank; attaching it in alignment with the crank C, and connecting its journals to the oscillating shafts 7, 8 and 9 in such a manner that the desired movement of the anodes is effected by the non-conducting master crank, thus maintaining the spaced embracing or straddling relation between the anodes and the rod journals at all times.

Such a master crank is shown in Figs. 1, 3 and 5, and may consist of a non-conducting material, such, for example, as molded plastic, methyl-methacrylate being a good example, although obviously any suitable nonconducting rigid material may be used. As shown, the master actuator crank comprises three disk-like members 50, 51 and 52, the disk 50 being rigidly connected with a hub 55 adapted to be clamped to the lower end of the crankshaft C, as, for example, by a clamping screw 56. This permits aligning the crank journals 60, 61 and 62 which are preferably spaced in 120 angular relation, as are the journals E, and which are arranged to rigidly hold their positions and that of the disks, thus forming in effect a crank having three throw bearings.

Each of the actuating journals 60, 61 and 62 may be connected by a rigid loop link with one of the anodecarrying shafts.

Referring to Fig. 3, one of the guide journals of the master crank as at 60 is shown as slidably and closely embraced by a loop member having rigid parallel sides 65, and connected by a rigid arm 67 with a hub 68 having a clamping and keyed connection with one of the anode carrying shafts, for example, 8.

The throw-bearing members 60 and 61 preferably are of sufficient size that when clamped to the supporting disks 50, 51 and 52, they may rigidly support and align these disks. The third and lower throw-bearing member 62 may be merely rigidly attached to the lower disk, but is embraced by a guide loop arm, and moves it as do the others. Thus, when the master crank is in position it acts to follow the crankshaft C and its journalbearing members 60, 61 and 62 and thus cause the shafts 7, 8 and 9 to oscillate with their anodes, at all times maintaining the same precise angular relation of each anode with one of the actuating members 65, 66 or 67, connected with the master crank. For example, the member 65 maintains the same angular relationship to the key-way in the shaft 8 as that of the anodes 32, and the master crank member 60 is aligned with two, that is, one pair of the journal bearings E.

For cranks of different throw (or piston stroke) the actuating members 60, 61 and 62 of the master crank may be adjusted radially. As shown, these members are secured by screws 63 which may pass through slots 64 in the disks 50, 51 and 52, and which allow adjusting the master crank journals toward or away from the center of the crank.

To steady the lower ends of the bus-bar shafts, I have shown a cross bracing member in the form of a disk having bearing openings embracing these shafts as at 81, 82, 83 and 84. A central opening may rotatably embrace the hub 55 of the master crank. This member 80 is of non-conducting material, or may be of metal suitably insulated to avoid current passing through it.

It will be seen that the principle of operation of the structure thus far described is that of effecting angular movement of the bus-bar elements or shafts, with their rigidly attached bifurcated anode members, in such a manner that the forked anodes will follow the revolving connecting rod journals in spaced relation to them.

Further, it is important that the effecting of this angular movement by means of an insulated member shall cause the angular movement to precisely follow the axis and surface of the connecting rod journals in their circular orbits as the crankshaft revolves.

Instead of using an insulated master crank having journal surfaces, each axially aligned with one or more of the connecting rod journals and connected to and oscillating the bus-bar carrier shaft for one or a pair or more of the anodes, I may accomplish the same general purpose by utilizing the surface of one of the aligned connecting rod journals for each pair or set of anodes. To this end I again use a follower member of insulating or non-conducting material and effect the angular movement of the anode bus-bar or shaft by the movement of one of the associated connecting rod journals.

A satisfactory and simple device for this purpose, and which may be used instead of the master crank, above described, comprises a pair of parallel rigid arms connected with a suitable hub on the bus-bar shaft and arranged to slidingly close contact the connecting rod journal surface at the radius, or at least adjacent one end of the connecting rod journal. One such actuator will obviously cause the effective angular motion of the supporting bar or shaft, which may in turn cause one, two or more bifurcated anode members to follow axially aligned connecting rod journals. One such actuator will obviously cause the effective angular motion of the supporting bar or shaft, which may in turn cause one, two or more bifurcated anode members to follow axially aligned connecting rod journals.

A form of such a device is shown in Figs. 6 to 9, in which in Fig. 6 the adjacent or middle pair of connecting rod journals E of the crankshaft are shown, and anode members are mounted on the bus-bar shaft 9, being connected to a hub 92 which is keyed or otherwise angularly fixed on this shaft. In this case the hub is modified from those shown in Fig. 1, and extends upwardly from a plane of the bottom edge of the two anode members 90, leaving room beneath the hub and the anode arms for the actuator guide member.

The actuator guide for oscillating the shaft 9 causing the anode 90 to follow the aligned journals E, while maintaining them spaced therefrom, may comprise a pair of parallel rigid blades 100 jonied at 102 with a hub 104 fixed to the shaft 9, as is the case with the anodes whose hubs 92 may be adjusted along the carrier bar or shaft 9 and secured as by screws 95 clamping against suitable keys. The hub 104 of the actuator may be keyed to the shaft and the screw 105 may be clamped against the key to hold the actuator in adjusted position.

The parallel arms 100 may be made of any suitable nonconducting material such as that of which the master crank may be made. Here again, a plastic material known as Lucitehas proven satisfactory. These guide arms 100 are preferably thin and flat except they may be tapered to a greater thickness at the outer sides, while at the inner side the edges are brought down to narrow or sharp knife edges 101 which contact opposite sides of the journal surface E, as shown particularly in Fig. 8.

The arms 100 are preferably separate from the adjacent anode arms 90, but it will be seen that as they slidingly contact with the revolving journal, the shaft 9 and both anodes 90 will be caused to maintain the same angular relation with, and spaced from, the journals E.

The outer ends of the arms 100 may be connected by a removable hooked member or wire indicated at 107, if desired, to mutually brace these members.

It will be seen that one actuator guide may thus effectively cause the parallel anode arms to move with and in spaced relation from two or more aligned journal surfaces in the same fashion that the master crank effects the angular motion of two or more of the anodes 30, 31 or 32, as described,

The anodes are preferably spaced from a quarter to a half inch away from the surface of the journal, and their upper and lower edges are correspondingly spaced from the surfaces of the crank arms and counter-balances of the crankshaft. Thus, there is room above or below any one pair of anode arms for positioning the actuator guide arms 100.

These arms may engage the curve or radius of the jour' nal surface where any line which may be formed during the plating by reason of the contact of these edges is of least possible consequence and results in the least defacement of the journal surface being plated. Obviously, 4

only one of the pair or group of aligned journal surfaces will be thus affected.

Having thus described my invention, what I claim is: 1. An apparatus for simultaneously electroplating the main journal surfaces and a plurality of axially aligned connecting-rod journal surfaces of a crankshaft, comprising inicombination, a container for the plating bath, means for suspending and turning a crankshaft about its main axis within the plating bath, movable anodes having elongated flat parallel arms spaced apart for straddling individual journal surfaces, means supporting and moving the anodes with an oscillating motion about a fixed axis parallel to the suspended crankshaft axis, said means including a supporting bar for a plurality of anodes positioned adjacent to aligned journal bearings, means rigid with each said bar and for connection with the crankshaft so as to follow the path of revolution of an aligned set of journal bearings and to effect the oscillation of the supporting bar so that each anode may move in constantly spaced relationship to its associated journal bearing as it revolves, anodes arranged for positioning adjacent to and spaced from each main bearing, and current-conducting elements connected with the crankshaft and all of said anodes.

2. An apparatus for simultaneously electro-plating the main journal surfaces and axially aligned connecting rod journal surfaces of a crankshaft, comprising a container for a plating bath. means for suspending and turning the crankshaft in the bath, anodes having elongated fiat surfaces parallel with the axis of the connecting rod journals, supporting bars rotatable on fixed axes parallel with the crankshaft axis and on which said anodes are mounted, means for holding the anodes rigidly on said rods at different longitudinal positions according to the spacing of the connecting rod journals,

a non-conducting rigid element for connecting the crank shaft with each of said supporting bars and movable by the turning of the crankshaft to maintain said anode surfaces at all times at predetermined spaced distances from their adjacent revolving journal surfaces by oscillating the supporting bars and anodes in synchronism with the crankshaft revolution.

3. An apparatus for simultaneously electroplating main journal surfaces and connecting-rod journal surfaces of a crankshaft comprising means for suspending and turning the crankshaft on its main axis in a plating bath, anodes each having surfaces adjacent to the main journal surfaces, anodes for the connecting-rod journal surfaces comprising bifurcated parallel members having elongated flat surfaces positioned and spaced apart for extending on opposite sides of and spacedlfrom the surfaces of said rod journals, rigid bars each oscillating about an axis parallel to the suspended crankshaft main axis for supporting the last-named anodes, and a sepa rate insulated master crank member having means for mounting it upon and for rotating with said crankshaft and having bearings aligned with and adapted to be connected to and operate in unison with the crankshaft journals, rigid parallel arms connected to the oscillating supporting means for the anodes and embracing said master crank bearings to cause the anodes to follow the journal surfaces in constantly spaced relationship thereto.

4. An apparatus for electro-plating journal surfaces of multiple throw crankshafts comprising means for suspending a crankshaft vertically in a plating bath, including a supporting frame and a rotatable crankshaftcarrying member above the bath, a plurality of dependent current-conducting bus-bars, one of .which is stationary, bearings on the frame for rotatably supporting the others of the bus-bars, means for maintaining the bus-bars parallel with the suspended crankshaft axis, anode elements vertically adjustably fixedto the stationary bus-bar and having a surface projecting to a fixed position adjacent to each main journal surface and extending vertically and parallel with the adjacent journal surface for the greater portion of the axial length of said surface, bifurcated anode members each having a pair of arms straddling and presenting an elongated fiat surface adjacent to and spaced from a throw-journal surface and each being rigidly secured to one of the rotatable bus-bars, a master crank element having means for coaxially securing it on the crankshaft, and having journal surfaces each aligned with a throw-journal surface, and a rigid follower connected with each rotatable busbar and engaging a master crank journal surface for oscillating the bus-bar to cause the aligned connected bifurcated anode to follow its throw-journal.

5. An apparatus for electro-plating journal surfaces of multiple throw crankshafts comprising means for suspending a crankshaft vertically in a plating bath, including a supporting frame and a rotatable crankshaftcarrying member above the bath and bearings on the frame, a plurality of dependent current-conducting busbars supported by said bearings and extending parallel with the crankshaft axis when suspended in the bath, anode elements fixed to one of the bus-bars and having a surface projecting to a fixed position adjacent to each main journal surface, bifurcated anode members each having a pair of arms and each arm of which presents its inner surface adjacent to and spaced from a throw-journal surface and each anode member being rigidly secured to another of the bus-bars, said last-mentioned busbar being rotatably mounted for oscillation on an axis parallel to the crankshaft axis a master crank element having means for connection with the crankshaft so as to revolve with it and having an insulated throw-journal surface aligned with a throw-journal surface of the crankshaft and a rigid follower embracing said insulated surface and connected with the last-named bus-bar for oscillating it to cause the connected bifurcated anode to follow its throw-journal and to maintain its spaced relation thereto.

6. An apparatus for simultaneously electro-plating the main journal surfaces and connecting-rod journal surfaces of a multiple-throw crankshaft, comprising means for suspending and turning the crankshaft about its main axis and within a plating bath, fixed anodes spaced from and adjacent to the main journal surfaces. movable anodes having parallel arms spaced for straddling and presenting elongated fiat surfaces adjacent to and spaced from the connecting-rod journal surfaces, supporting bars each mounted to oscillate on an axis parallel tothe main axis and on which said movable anodes are mounted, current-carrying means leading to the last-named anodes, and means for oscillating said supporting bars to maintain uniform spaced relation between the anodes and the adjacent journal surfaces, said means comprising an insulated master crank having means for rigidly mounting it upon and coaxially with the crankshaft and having journals aligned with the w crankshaft journals, and rigid arms engaging said insulated crank journals and fixed on said supporting bars to oscillate the bus-bars consequent upon rotation of the crank shaft being plated.

References Cited in the file of this patent UNITED STATES PATENTS v Totten July 31, Garling Oct. 4,

Kaufman June 17,

Millard June 14, Birkenkotter Nov. 21,

FOREIGN PATENTS France Sept. 1, 

1. AN APPARATUS FOR SIMULTANEOUSLY ELECTROPLATING THE MAIN JOURNAL SURFACES AND A PLURALITY OF AXIALLY ALIGNED CONNECTING-ROD JOURNAL SURFACES OF A CRANKSHAFT, COMPRISING IN COMBINATION, A CONTAINER FOR THE PLATING BATH, MEANS FOR SUSPENDING AND TURNING A CRANKSHAFT ABOUT ITS MAIN AXIS WITHIN THE PLATING BATH, MOVABLE ANODES HAVING ELONGATED FLAT PARALLEL ARMS SPACED APART FOR STRADDLING INDIVIDUAL JOURNAL SURFACES, MEANS SUPPORTING AND MOVING THE ANODES WITH AN OSCILLATING MOTION ABOUT A FIXED AXIS PARALLEL TO THE SUSPENDED CRANKSHAFT AXIS, SAID MEANS INCLUDING A SUPPORTING BAR FOR A PLURALITY OF ANODES POSITIONED ADJACENT TO ALIGNED JOURNAL BEARINGS, MEANS RIGID WITH EACH SAID BAR AND FOR CONNECTION WITH THE CRANKSHAFT SO AS TO FOLLOW THE PATH OF REVOLUTION OF AN ALIGNED SET OF JOURNAL BEARINGS AND TO EFFECT THE OSCILLATION OF THE SUPPORTING BAR SO THAT EACH ANODE MAY MOVE IN CONSTANTLY SPACED RELATIONSHIP TO ITS ASSOCIATED JOURNAL BEARING AS IT REVOLVES, ANODES ARRANGED FOR POSITIONING ADJACENT TO AND SPACED FROM EACH MAIN BEARING, AND CURRENT-CONDUCTING ELEMENTS CONNECTED WITH THE CRANKSHAFT AND ALL OF SAID ANODES. 